Currently, washing method of an impeller washing machine is to achieve cleaning by special water flow generated from impeller rotation or simultaneous rotation of the impeller and inner tub to overturn the clothing and pose force on it during overturn so that the clothing can be washed repeatedly through self friction and friction with impeller and inner tub wall. Impeller of the impeller washing machine has various shapes such as plate, bar, bowl shapes, etc.; regardless of shape change, ultimate goal of the impeller is to improve cleanliness and reduce clothing intertwining. However, high cleanliness and low intertwining rate are contradictory. Usually, the cleanliness will increase with high intertwining rate, or the cleanliness decrease with low intertwining rate. Existing impeller washing machine has such disadvantages as large water and detergent consumption, long washing time, clothing intertwining and knotting, uneven washing and deformation; or, clothing washing is realized via impact force of water flow formed by centrifugal force generated by inner tub rotation. Usually, clothing is washed as a whole. Although water flow has an effect on washing, clothing cannot be dispersed while will be intertwined as a whole.
In order to improve cleanliness, the impeller is required to rotate rapidly at large angles during washing. Clothing will be driven by water flow generated by centrifugal force to move along the same direction rapidly. Eventually, clothing will be intertwined, torn and damaged, especially high-end clothing which is more readily damaged; moreover, in case of simply relying on water flow during washing, the mode of movement is simple and fixed, resulting in low overturn efficiency of clothing in the tub. Hence, more times of washing is required to be conducted to achieve washing effects of the clothing.
Besides, when the washing machine is running, impeller rotates or oscillates to generate ring-shaped water flow, and movement of clothing in the tub depends on fluid motion or fluidic power. In order to realize required ring-shaped overturn mode, it is also necessary that automatic washing machine with impeller at the bottom is filled with washing liquid. Height of the washing liquid shall be able to completely submerge fabrics put into the washing drum. Hence, it will consume large quantity of water. In addition, since the quantity of washing liquid is large, more detergent must be used to achieve enough concentration. As a result, the washing cost is high and water resources will be polluted to a certain extent.
China Patent Publication No. CN2898085Y discloses an impeller of washing machine, comprising a round underpan and water string set on the underpan, which is characterized in that the underpan has high circumference and low center, forming a concave curved sphere. The water string comprises a central water string, a primary water string and a secondary water string, and the central water string is positioned in the middle of the underpan; the primary water string is arranged radially on the underpan, on both sides thereof, a bevel tilting outwards is positioned; the secondary water string is also arranged radially on the underpan, on both sides thereof, a bevel tilting outwards is positioned; the primary water string is spaced from the secondary water string, the central water string is higher than the primary water string which is higher than the secondary water string.
U.S. Pat. No. 1,704,932A discloses a washing machine, comprising a dolly or agitating member operative from and by means of a shaft passing up through the bottom of the tub or container fins, integrating with radially arranged blades or baffle members and an intermediate surface inclined or curved upwardly from its peripheral edge, that the resultant action of the dolly or agitator; as it is alternately oscillated is to cause the articles being washed to be moved toward the center of the dolly or agitating member and upwardly and thence outwardly and downwardly; or in other words impart to such articles a slow whirl like motion radially of the dolly or agitator and thereby more effectively cleanse the articles, by constant agitation and the forcing of air and water through the articles. This invention has reference to washing machines, and it has for its principal object to improve the dolly or agitating means, whereby to produce a more effective and improved washing action on the articles deposited in the tub or container thereof.
EP Patent No. EP0837171B1 discloses an automatic washer for washing clothes, the automatic washer comprising: an imperforate wash tub, a perforated wash basket having a cylindrical side wall, provided within and rotatable relative to the wash tub, a rotatable washplate with a bottom plate, a peripheral wall and a centrally disposed annular mounting collar, provided within and rotatable relative to the wash basket, a drive system connected to the wash basket and the wash tub for rotating the wash basket and the wash plate, and a least two diametrically opposed ripples provided on and extending upwardly from the bottom plate of the wash plate, characterised in that each ripple has a saddle shaped surface contour defining opposing sloped walls which extend respectively radially inwardly and radially outwardly form a low point substantially midway between the peripheral wall and the outer edge of the annular collar and in that the peripheral wall is substantially perpendicular to the bottom plate, The radially outwardly extending sloped wall of the ripples rising to meet the upper part of the peripheral wall, and in that an annular sealing lip is provided around the outside of the peripheral wall, extending outwardly substantially perpendicularly from the top edge of the peripheral wall to the cylindrical side wall of the wash basket.
U.S. Pat. No. 4,068,503A discloses an improved agitator means for use with an automatic washer having a clothes washing receptacle and drive means for driving an agitator in an oscillatory fashion. The improved agitator means of the present invention is a double action agitator and includes a lower agitator element which is engageable with the drive means for oscillation about an axis in the usual manner and an upper agitator element which is coaxial with the lower element and is coupled to the drive shaft by means of a one-way clutch for unidirectional rotation about the axis of the agitator. The upper agitator element is provided with auger-like vane means for urging clothes within the receptacle downwardly toward the lower agitator element where they are contacted by a set of generally vertically-extending vanes disposed about the skirt portion of the lower agitator element. In effect, therefore, the upper agitator element acts to continuously feed clothes downwardly along the barrel of the agitator where they come under the influence of the oscillating vertically positioned vanes of the lower agitator element which direct the clothes radially outwardly toward the periphery of the basket, and eventually upwardly and back to the barrel of the upper agitator element, completing a repeating rollover cycle which is extremely efficient for securing a uniform scrubbing contact of the clothes with the wash liquid.
In witness whereof, the invention is provided.